An antipope (Latin: antipapa) is a person who, in opposition to a sitting Bishop of Rome, makes a widely accepted claim to be the Pope.[1] In the past, antipopes were typically those supported by a fairly significant faction of cardinals and kingdoms. Persons who claim to be the pope but have few followers, such as the modern sedevacantist antipopes, are not generally classified as antipopes, and therefore are ignored for regnal numbering.